As part of patch 2.1, those playing the Starter Edition -- a free version of StarCraft II that allows access to a limited number of features -- will have access to the Arcade, effectively allowing them to play all custom game modes and maps without having to purchase a copy of the game. Among the content found on the Arcade is the Warcraft 4 fan mod that recently made headlines.
In addition, the single-race restriction is being lifted, and Starter Edition players will be able to freely choose from Protoss, Zerg, and Terran.
These moves come as the latest attempts to expand the StarCraft player base. The Starter Edition replaced the Wings of Liberty demo in 2011, and earlier this year the new spawning feature was introduced, allowing those who own the game to play with friends who do not.